Sheet feeder with transversely translatable floating final height adjustment block

ABSTRACT

An assembly (100) and method for bottoming feeding sheets from a stack of sheets to a top-feed sheet feeding mechanism (F) on a device (P), such as a copy machine. The assembly (100) includes a sheet feeder (200), a transport arm (300), and a final height adjustment block (420) translatably attached to and extending along the distal end (302) of the transport arm (300) for limited transverse (T) translation relative to the machine direction (MD).

BACKGROUND

Devices such as printers and copy machines are typically equipped with a top-feed bypass sheet feeder for copying onto sheets that are inconvenient or difficult to feed from the regular paper trays inside the printer or copier. These top-feed bypass sheet feeders typically include a presence sensor for controlling the feeding of sheets into the bypass sheet feeder based upon sensed presence of a sheet in proper feed position. The bypass trays are biased or periodically driven upward so that the top of the sheet stack on the bypass tray remains in proper feed position as the sheets on the top of the stack are fed into the device.

Such bypass sheet feeders are not well suited for handling larger jobs as they are typically designed to handle less than 100 sheets, and do not accommodate the loading of additional sheets to the stack ad libitum during a run. Hence, for long runs an operator must constantly monitor the process and add additional sheets to the stack when and only when the bypass tray is empty.

One attempt to overcome these bypass sheet feeder limitations is described in U.S. Pat. No. 8,490,964, wherein a bottom-feed sheet feeder is equipped with a pivoting delivery table to feed sheets to the bypass sheet feeder. While generally effective for allowing unmonitored, long run use of a bypass sheet feeder, the weight of the pivoting delivery tray has been found to exert excessive downward force upon the bypass sheet feeder, resulting in frequent feed failures because the bypass sheet feeder is prevented from raising the delivery tray as necessary to trigger the “paper available” sensor. U.S. Pat. No. 8,490,964 recognizes this failing and attempts to remediate the problem by providing an adjustable counterbalancing mechanism for reducing the effective weight of the delivery table. Due to the complexity of setting the counterbalancing mechanism to provide the proper counterbalancing weight for each production run, and need for periodic resetting of the counterbalancing mechanism during a run, the assembly has enjoyed but tepid reception.

Accordingly, a need exists for an assembly capable of quickly, easily and reliably allowing unmonitored, long run use of a bypass sheet feeder on a copier, printer or similar electronic device.

SUMMARY OF THE INVENTION

A first aspect of the invention is an assembly adapted to bottom-feed sheets from a stack of sheets to a top-feed sheet feeding mechanism on a device, such as a copy machine. The assembly includes a sheet feeder, a transport arm, and a final height adjustment block. The sheet feeder has a hopper for holding a stack of sheets and at least one feed belt operable for advancing a bottom-most sheet from the stack of sheets. The transport arm is attached to the sheet feeder for receiving sheets advanced by the at least one feed belt at a proximal end of the transport arm and transporting the received sheets in a machine direction to a distal end of the transport arm. The final height adjustment block is translatably attached to and extends along the distal end of the transport arm for limited transverse translation relative to the machine direction.

A second aspect of the invention is a method of feeding sheets to an electronic printing device when the printing device includes at least (i) a sheet feed mechanism for pulling a top sheet from a stack of sheets into the electronic printing device, (ii) an actuatable support for the stack of sheets operable when actuated for lifting the stack of sheets into a position suitable for pulling of a top sheet into the electronic printing device, and (iii) a presence sensor for sensing presence of a sheet in a position suitable for being pulled into the electronic printing device by the sheet feed mechanism. The method includes the steps of (-)placing a transport arm, equipped with a transversely floating final height adjustment block and extending from a bottom-feed sheet feeder, into operable sheet feeding engagement with the sheet feed mechanism on the electronic printing device, with the transversely floating final height adjustment block resting upon the support for the stack of sheets such that lifting actuation of the support for the stack of sheets transversely translates the floating final height adjustment block relative to the transport arm, and (-)thereafter feeding individual sheets from the bottom-feed sheet feeder to the sheet feed mechanism on the electronic printing device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side perspective view of one embodiment of the invention operationally interfacing with the bypass sheet feeder of a copier.

FIG. 2 is an enlarged front perspective view of the transport arm and final height adjustment block components of the invention depicted in FIG. 1.

FIG. 3 is a top view of the transport arm and final height adjustment block components of the invention depicted in FIG. 2.

FIG. 4 is a side view of the transport arm and final height adjustment block components of the invention depicted in FIG. 2.

FIG. 5 is an enlarged side perspective view of the area depicted in FIG. 1 where the transport arm and final height adjustment block of the invention interface with the bypass sheet feeder of the copier.

FIG. 6 is a side view of the area depicted in FIG. 5.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Definitions

As utilized herein, including the claims, the term “machine direction” means the direction in which a sheet travels.

As utilized herein, including the claims, the term “cross machine direction” means the direction in the plane defined by a traveling sheet which is perpendicular to the direction in which the sheet travels.

As utilized herein, including the claims, the term “transverse direction” means the direction perpendicular to both the machine direction and the cross machine direction (i.e., direction of sheet thickness).

As utilized herein, including the claims, the term “generally cuboidal” means having an overall cuboidal shape, and including those with chamfered or bullnose corners, limited cutouts, shoulder extensions, etc.

As utilized herein, including the claims, the term “electronic printing device” includes any and all electronic devices capable of imprinting, marking, embossing or otherwise placing indicia on a sheet, including specifically but not exclusively, copiers, printers and braille embossers.

Nomenclature Table REF NO. DESCRIPTION 100 Assembly 200 Sheet Feeder 210 Hopper 220 Feed Belt 290 Support Stand 300 Transport Arm 301 Proximal End of Transport Arm 302 Distal End of Transport Arm 310 Transport Arm Pivot Locking Mechanism 400 Final Height Adjustment Module 410 Mounting Brackets 411 Proximal End of Mounting Brackets 412 Distal End of Mounting Brackets 419 Transverse Slots in Distal End of Mounting Brackets 420 Floating Final Height Adjustment Block 421 Leading Edge of the Floating Final Height Adjustment Block 422 Trailing Edge of the Floating Final Height Adjustment Block 423 Top Surface of Floating Final Height Adjustment Block 424 Chamfered Top Corner of Floating Final Height Adjustment Block 430 Pins or Shoulder Bolts 440 Roller on Floating Final Height Adjustment Block P Electronic Printing Device F Top-Feed Sheet Feeding Mechanism on the Electronic Printing Device with Lift Actuatable Support (e.g., Bypass Sheet Feeder) F_(R) Driven Feed Roller MD Machine Direction xMD Cross Machine Direction T Transverse Direction

Construction

Referring to FIG. 1, the first aspect of the invention is an assembly 100 adapted to bottom-feed sheets (not shown) from a stack of sheets (not shown) to a top-feed sheet feeding mechanism F on a device, typically an electronic printing device P such as the ubiquitous electronic copy machine.

The assembly 100 includes a sheet feeder 200, a transport arm 300, and a final height adjustment module 400.

The sheet feeder 200 can be any of the sheet feeders widely available from a number of sources, including those offered by Thiele Technologies under the Streamfeeder line of products. Exemplary sheet feeders 200 suitable for use in this invention include those described in U.S. Pat. Nos. 6,932,338 and 8,336,876, the disclosures of which are hereby incorporated by reference. Generally, the sheet feeder 200 has a hopper 210 for holding a stack of sheets and at least one feed belt 220 operable for advancing a bottom-most sheet from the stack of sheets.

As shown in FIG. 1, the sheet feeder 200 is preferably supported upon a height-adjustable support stand 290 equipped with lockable swivel casters for ease of transport. An initial height adjustment of the assembly 100 relative to an electronic printing device P can be achieved using the height adjustable support stand 290.

Referring to FIGS. 1, 5 and 6, the transport arm 300 is attached at a proximal end 301 to the sheet feeder 200 for receiving sheets advanced by the at least one feed belt 220. The transport arm 300 is operable for advancing the received sheets in a machine direction MD from the proximal end 301 of the transport arm 300 to the distal end 302 of the transport arm 300. The transport arm 300 is preferably pivotally attached to the sheet feeder 200 for allowing an initial height adjustment of the transport arm 300 on the assembly 100 into proper vertical registration with a top-feed sheet feeding mechanism F on an electronic printing device P, such as the bypass sheet feeder on a copy machine. A locking mechanism 310 is preferably provided for locking the transport arm 300 into position once the desired vertical registration relative to a top-feed sheet feeding mechanism F is achieved.

Referring to FIGS. 2-6, the final height adjustment module 400 includes a floating final height adjustment block 420 attached at and extending along the distal end 302 of the transport arm 300 for limited pivoting about an axis extending in a cross machine direction xMD or translation in a transverse direction T relative to the transport arm 300.

The floating final height adjustment block 420 can have substantially any geometrical shape so long as the floating final height adjustment block 420 is effective for facilitating advancement of sheets onto and across the floating final height adjustment block 420 from the transport arm 300 into feeding position against the sheet feed mechanism F of an electronic printing device P. In a preferred embodiment the floating final height adjustment block 420 is generally cuboidal with a machine direction MD length of 2 to 10 cm, a cross machine direction xMD width of 10 to 100 cm, and a transverse direction T thickness of 0.5 to 10 cm.

The floating final height adjustment block 420 preferably has a weight of less than 1000 grams, more preferably less than 700 grams and most preferably less than 500 grams. A floating final height adjustment block 420 having a weight of substantially greater than 1000 grams can inhibit lifting of the floating final height adjustment block 420 into proper sheet feeding position by the lift actuatable support of a top-feed sheet feeding mechanism F on an electronic printing device P as such mechanisms are generally designed and constructed to lift about 100 sheets of standard sized paper which would weigh about 500 grams.

When the floating final height adjustment block 420 is pivotally attached to the transport arm 300, the floating final height adjustment block 420 is preferably constrained against pivoting more than about 5° as excessive pivoting can interfere with reliable and consistent advancement of sheets onto and over the floating final height adjustment block 420.

The floating final height adjustment block 420 is preferably constrained for transverse T translation relative to the transport arm 300 a distance of between about 2 to 20 mm, most preferably between about 5 to 10 mm Translation of a distance greater than about 20 mm can interfere with reliable and consistent advancement of sheets onto and over the floating final height adjustment block 420, while translation of a distance less than about 2 mm is insufficient to reliably and consistently ensure that the entire weight of the transport arm 300 is resting upon and supported by the actuatable support of a top-feed sheet feeding mechanism F on an electronic printing device P.

The floating final height adjustment block 420 may be conveniently attached at the distal end 302 of the transport arm 300 using a pair of side mounting brackets 410 with a proximal end 411 of each side mounting bracket 410 attached to the transport arm 300 and a distal end 412 of each side mounting bracket 410 projecting a distance in the machine direction MD beyond the distal end 302 of the transport arm 300.

One particular structure for providing limited transverse T translation of the floating final height adjustment block 420 relative to the transport arm 300 is to mount the floating final height adjustment block 420 to each of the side mounting brackets 410 with dual pin-in-slot linkages. Referring to FIG. 4, a pair of machine direction MD spaced pins 430 project in the cross machine direction xMD from each side of the floating final height adjustment block 420. These pins 430 are supported within corresponding transversely T elongated slots 419 in each of the mounting brackets 410.

The top surface 423 of the floating final height adjustment block 420 is preferably in substantial planar alignment with the upper transport surface (unnumbered) of the transport arm 300 and is reasonably flat and smooth for facilitating advancement of sheets onto and across the floating final height adjustment block 420 from the transport arm 300 into feeding position against the sheet feed mechanism F of an electronic printing device P. Referring to FIGS. 2, 3 and 4, the upper corner 424 of the trailing edge 422 of the floating final height adjustment block 420 is preferably chamfered for facilitating advancement of sheets onto the floating final height adjustment block 420 from the transport arm 300 even when the floating final height adjustment block 420 is transversely T translated upward relative to the transport arm 300 such that the top surface 423 of the floating final height adjustment block 420 is transversely T spaced a distance above the upper transport surface (unnumbered) of the transport arm 300.

Referring to FIGS. 2-6, the floating final height adjustment block 420 may be equipped with an undriven roller 440 rotating about a cross machine direction xMD axis and projecting a distance above the top surface 423 of the floating final height adjustment block 420 proximate the leading edge 421 of the floating final height adjustment block 420, for registration with a driven feed roller F_(R) on the sheet feed mechanism F of an electronic printing device P in order to facilitate driven advancement of sheets into the electronic printing device P by the driven feed roller F_(R).

Use

The assembly 100 is suited for feeding sheets to an electronic printing device P equipped with (-)a sheet feed mechanism F that pulls a top sheet from a stack of sheets into the electronic printing device P, (-)a support for the stack of sheets actuatable for lifting the stack of sheets into a position suitable for pulling of a top sheet into the electronic printing device P, and (-)a presence sensor for sensing presence of a sheet in a position suitable for being pulled into the electronic printing device P by the sheet feed mechanism F.

Use of the assembly 100 to feed sheets to such an electronic printing device P includes the steps of (-)placing the transport arm 300 of the assembly into operable sheet feeding engagement with the sheet feed mechanism F on the electronic printing device P, with the transversely floating final height adjustment block 420 resting upon the support for the stack of sheets such that lifting actuation of the support for the stack of sheets transversely translates the floating final height adjustment block 420 relative to the transport arm 300, and (-)thereafter feeding individual sheets from the bottom-feed sheet feeder 200 to the sheet feed mechanism F on the electronic printing device P.

The assembly 100 is preferably configured and arranged, and positioned relative to the sheet feed mechanism F on the electronic printing device P, such that lifting actuation of the support for the stack of sheets does not pivot the transport arm 300 relative to the bottom-feed sheet feeder 200. The assembly 100 is also preferably configured and arranged, and positioned relative to the sheet feed mechanism F on the electronic printing device P, such that the transport arm 300, inclusive of the floating final height adjustment block 420, applies a downward force of less than 5 Newton, preferably less than 3 Newton and most preferably less than 2 Newton upon the support for the stack of sheets. Application of a downward force of substantially greater than 5 Newton upon the support for the stack of sheets can inhibit lifting of the floating final height adjustment block 420 into proper feeding position by the support for the stack of sheets on the electronic printing device P as such mechanisms are generally designed and constructed to lift about 100 sheets of standard sized paper which would exert a downward force of about 5 Newton. 

I claim:
 1. An assembly adapted to bottom-feed sheets from a stack of sheets to a top-feed sheet feeding mechanism on a device, the assembly comprising: (a) a sheet feeder having a hopper for holding a stack of sheets, and at least one feed belt operable for advancing a bottom-most sheet from the stack of sheets, (b) a transport arm attached to the sheet feeder for receiving sheets advanced by the at least one feed belt at a proximal end of the transport arm and transporting the received sheets in a machine direction to a distal end of the transport arm, and (c) a final height adjustment block translatably attached to and extending along the distal end of the transport arm for limited transverse translation relative to the machine direction.
 2. The assembly of claim 1 wherein the final height adjustment block is limited to transverse translation of between 2 and 20 mm.
 3. The assembly of claim 1 wherein the final height adjustment block is constrained from pivoting about an axis extending in a cross machine direction.
 4. The assembly of claim 3 wherein the final height adjustment block is constrained from pivoting more than 5° about an axis extending in a cross machine direction.
 5. The assembly of claim 1 wherein the final height adjustment block (i) has a top surface, (ii) receives sheets transported by the transport arm, and (iii) has a chamfered top corner proximate the distal end of the transport arm for guiding leading edges of sheets received by the final height adjustment block onto the top surface of the final height adjustment block.
 6. The assembly of claim 1 wherein the final height adjustment block is generally cuboidal with a machine direction length of 2 to 10 cm, a cross machine direction width of 10 to 100 cm, and a transverse direction thickness of 0.5 to 10 cm.
 7. The assembly of claim 1 wherein the final height adjustment block weighs less than 1000 grams.
 8. The assembly of claim 1 wherein the final height adjustment block weighs less than 700 grams.
 9. The assembly of claim 1 wherein the final height adjustment block weighs less than 500 grams.
 10. The assembly of claim 5 wherein the top of the final height adjustment block is flat and smooth.
 11. The assembly of claim 1 further comprising an undriven roller, rotating about an axis extending in the cross machine direction, attached to the final height adjustment block and projecting in a transverse direction above the top of the final height adjustment block for contacting sheets transported over the final height adjustment block.
 12. The assembly of claim 11 wherein the undriven roller attached to the final height adjustment block is configured and arranged to cooperate with a driven sheet feeder roller on an electronic printing device for feeding sheets into the electronic printing device.
 13. A method of feeding sheets to an electronic printing device that includes a sheet feed mechanism for pulling a top sheet from a stack of sheets into the electronic printing device, a support for the stack of sheets actuatable for lifting the stack of sheets into a position suitable for pulling of a top sheet into the electronic printing device, and a presence sensor for sensing presence of a sheet in a position suitable for being pulled into the electronic printing device by the sheet feed mechanism, the method comprising the steps of: (a) placing a transport arm equipped with a transversely floating final height adjustment block and extending from a bottom-feed sheet feeder into operable sheet feeding engagement with the sheet feed mechanism on the electronic printing device, with the transversely floating final height adjustment block resting upon the support for the stack of sheets such that lifting actuation of the support for the stack of sheets transversely translates the floating final height adjustment block relative to the transport arm, and (b) thereafter feeding individual sheets from the bottom-feed sheet feeder to the sheet feed mechanism on the electronic printing device.
 14. The method of claim 13 wherein lifting actuation of the support for the stack of sheets does not pivot the transport arm relative to the bottom-feed sheet feeder.
 15. The method of claim 13 wherein the transport arm, inclusive of the transversely floating final height adjustment block, applies a downward force of less than 5 Newton upon the support for the stack of sheets after the placement step.
 16. The method of claim 13 wherein the transport arm, inclusive of the transversely floating final height adjustment block, applies a downward force of less than 3 Newton upon the support for the stack of sheets after the placement step.
 17. The method of claim 13 wherein the transport arm, inclusive of the transversely floating final height adjustment block, applies a downward force of less than 2 Newton upon the support for the stack of sheets after the placement step. 